Systems and methods for ablation of occlusions within blood vessels

Abstract

Wire systems for the ablation of occlusions within blood vessels are provided. Systems include one or more wires configured for percutaneous insertion in a blood vessel, the wires configured to ablate an occlusion within the blood vessel. In some embodiments, a wire is gradually tapered near its distal end so that it can be used to pierce occlusions. In some cases, it may be used to dilate existing microchannels within occlusions. In some embodiments, a capture device is inserted towards the occlusion from either the same or opposite side as the tapered wire, and is used to draw the wire through the occlusion.

What is claimed is: 
     
       1. A multiple-wire system for obtaining access through an occlusion within a blood vessel, comprising:
 a first wire configured for percutaneous insertion in the blood vessel towards a proximal surface of the occlusion, the first wire comprising:
 a first outer wire having a proximal end, a distal end, and a generally cylindrical outer surface, wherein the first outer wire includes an opening adjacent the distal end, an opening adjacent the proximal end, and a central lumen communicating therebetween; 
 a first middle wire configured for insertion in the blood vessel through the central lumen of the outer wire, the first middle wire having a proximal end, a distal end and a generally cylindrical outer surface, wherein the first middle wire includes an opening adjacent the distal end, an opening adjacent the proximal end, and a central lumen communicating therebetween, wherein the first middle wire is longer than the first outer wire; and 
 a first inner wire having a proximal end, a distal end, and a gradually tapered portion adjacent the distal end, wherein the first inner wire gradually tapered portion is configured to penetrate and pass through the occlusion, and wherein the gradually tapered portion comprises a first magnet having a diameter no greater than the gradually tapered portion; and 
 
 a capture device configured for percutaneous insertion in the blood vessel towards a distal surface of the occlusion opposite the proximal surface, the capture device being operable to draw the distal end of the first wire to a position distal of the distal surface of the occlusion, wherein the capture device comprises a second magnet that is adapted to attract the first magnet. 
 
     
     
       2. The multiple-wire system of  claim 1 , wherein the gradually tapered portion tapers from a diameter of about 0.036 cm (0.014 inches) to a diameter of about 0.025 cm (0.010 inches) in a direction from the proximal end of the first inner wire towards the distal end of the first inner wire. 
     
     
       3. The multiple-wire system of  claim 1 , wherein the gradually tapered portion tapers from a diameter of about 0.036 cm (0.014 inches) to a diameter of about 0.020 cm (0.008 inches) in a direction from the proximal end of the first inner wire towards the distal end of the first inner wire. 
     
     
       4. The multiple-wire system of  claim 1 , wherein the gradually tapered portion tapers from a diameter of about 0.046 cm (0.018 inches) to a diameter of about 0.025 cm (0.010 inches) in a direction from the proximal end of the first inner wire towards the distal end of the first inner wire. 
     
     
       5. The multiple-wire system of  claim 1 , wherein the gradually tapered portion tapers from a diameter of about 0.053 cm (0.021 inches) to a diameter of about 0.036 cm (0.014 inches) in a direction from the proximal end of the first inner wire towards the distal end of the inner first wire. 
     
     
       6. The multiple-wire system of  claim 1 , wherein the capture device further includes a receptor having a distal opening, a proximal end and a channel leading from the distal opening toward the proximal end, wherein the first and second magnets are adapted to draw the distal end of the first wire into the channel. 
     
     
       7. The multiple-wire system of  claim 6  wherein the channel of the receptor tapers in a direction from the distal opening toward the proximal end of the receptor. 
     
     
       8. The multiple wire system of  claim 1 , wherein the capture device comprises:
 a second outer wire having a proximal end, a distal end, and a generally cylindrical outer surface, wherein the second outer wire includes an opening adjacent the distal end, an opening adjacent the proximal end, and a central lumen communicating therebetween; 
 a second middle wire configured for insertion in the blood vessel through the central lumen of the outer wire, the second middle wire having a proximal end, a distal end and a generally cylindrical outer surface, wherein the second middle wire includes an opening adjacent the distal end, an opening adjacent the proximal end, and a central lumen communicating therebetween, wherein the second middle wire is longer than the first outer wire; and 
 a second inner wire having a proximal end and a distal end, and wherein the second inner wire comprises the second magnet. 
 
     
     
       9. A method of obtaining access through an occlusion in a blood vessel, comprising:
 inserting a first wire into the blood vessel to a position where the distal end of the first wire is distal of a proximal surface of the occlusion, wherein the first wire comprises:
 a first outer wire having a proximal end, a distal end, and a generally cylindrical outer surface, wherein the first outer wire includes an opening adjacent the distal end, an opening adjacent the proximal end, and a central lumen communicating therebetween; 
 a first middle wire configured for insertion in the blood vessel through the central lumen of the outer wire, the second wire having a proximal end, a distal end and a generally cylindrical outer surface, wherein the first middle wire includes an opening adjacent the distal end, an opening adjacent the proximal end, and a central lumen communicating therebetween, wherein the first middle wire is longer than the first outer wire; and 
 a first inner wire having a proximal end, distal end and a gradually tapered portion adjacent the distal end, wherein the gradually tapered portion is configured to penetrate and pass through the occlusion, and wherein the gradually tapered portion comprises a first magnet having a diameter no greater than the gradually tapered portion; 
 
 inserting a capture device into the blood vessel to a position adjacent the distal end of the first wire; and operating the capture device to draw the distal end of the first wire to a position distal of a distal surface of the occlusion. 
 
     
     
       10. The method of  claim 9 , wherein the capture device is inserted into the blood vessel towards a distal surface of the occlusion opposite the proximal surface. 
     
     
       11. The method of  claim 9 , wherein operating the capture device includes operating a second magnet included on the capture device to attract the first magnet included on the first wire.